Efficacy of Selected Insecticide Mixtures for Bollworm and Tobacco Budworm Control, 1997

Thirteen treatments were evaluated at the Red River Research Station, Bossier City, LA, to determine their efficacy in controlling the bollworm/tobacco budworm (BW/TBW) complex on cotton. Plots were planted 9 May and were 4 rows X 100 ft on 40-inch centers. All plots had Temik 15 G (0.5 lb (AI)/acre) applied in-furrow at planting. The experimental design was a RCB with 4 replications. Prior to trial initiation, plots were oversprayed for cutworms on 6 Jun (Karate 1 EC at 0.025 lb (AI)/acre); boll weevils on 9, 13, 18 Jun and 3 Jul (Vydate C-LV at 0.25 lb (AI)/acre); BW/TBW on 27 Jun (Baythroid 2 EC at 0.03 lb (AI)/acre), and 11 Jul (Karate 1 EC at 0.03 lb (AI)/acre); and for aphids on 17 Jul (Provado 1.6°F at 0.047 lb (AI)/acre). Test materials were applied with a high-clearance sprayer equipped with a CO2 system for spraying small plots. Insecticide treatments were applied on 15, 22, 29 Jul, 5 and 14 Aug in 5.9 gpa at 60 psi with TX-3 hollow-cone nozzles spaced 20 inches apart (2 nozzles/row). Infestations of BW and TBW larvae and square damage were monitored on 18, 25 Jul, 1 and 11 Aug by examining 25 squares/plot. Following the trial, all plots were oversprayed for BW/TBW on 22 Aug with Karate 1 EC plus Curacron 8 EC at 0.028 + 0.75 lb (AI)/acre. Boll weevil eradication sprays with weekly applications of ULV Malathion (12 oz product/acre) were begun the week of 18 Aug. Yields were determined by mechanically harvesting the center 2 rows of each plot on 7 Oct.